'Putler,' 'Adolf Putin' Mocked for Seizing Crimea

History repeats itself, or at least that's the view from many on Twitter, reacting to what some are calling Russia's "dictator-like" military presence in Ukraine.

Hashtags and memes surfacing on social media today draw parallels between Russian President Vladimir Putin and Adolf Hitler, after troops in unmarked uniforms - but identified as Russians - essentially took control of Crimea.

In his request for the Russian Duma to authorize him to send troops into Ukraine, Putin cited the need to defend Russian citizens, "compatriots," and the Russian military installations in Crimea, an autonomous region of Ukraine whose population is primarily ethnic Russians.

For some, that has echoes of the the 1930s, when Hitler moved troops to what he referred to as Sudetenland, a region of the former Czechoslovakia whose population was primarily German.